[105.03] Constraining Galaxy Halo Shapes with Weak Lensing

C.O. Wright, T.G. Brainerd (Boston University)

We have run detailed Monte Carlo simulations to investigate
the weak gravitational lensing properties of galaxies with
finite, elliptically symmetric mass distributions. The
simulations match observational constraints as closely as
possible, e.g. faint galaxy number counts, the redshift
distribution of galaxies as a function of magnitude, the
luminosity function of galaxies, a range of reasonable halo
shapes, etc. The simulations also include the full effects
of multiple lensing events.

The shear pattern due to elliptically symmetric mass
distributions is anisotropic about the lens centers. We
quantify the level of anisotropy by comparing the mean shear
experienced by sources closest to the minor axes of the
lenses to that experienced by sources closest to the major
axes of the lenses, as a function of distance from the lens
center and azimuthal proximity to the symmetry axes.

In the context of a deep ground-based data set for which
photometric redshifts are available, we predict the
approximate survey areas necessary to detect an anisotropy
in the lensing signal at various levels of significance, in
the presence of various amounts of noise.